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deposits of sand and clay, ''put down when the land stood lower than 

 today, while the temperature was little different from that of today." 

 After Yanuxem's report of 1826, nothing more was done by the 

 State in the way of a survey until 1842. In that year, by authority 

 of the Legislature, Mr. Edmund Ruffin, of Virginia, was employed 

 to make an agricultural survey of the State. He conducted the work 

 with great ability, and his report is valuable not only as an agricul- 

 tural report, but also as a source of geological knowledge, especially 

 the discussion of the marl beds. He relied largely on characteristic 

 fossils in determining the age of the different marl beds investi- 

 gated. These marl beds were grouped into four classes : ( 1 ) The 

 Peedee bed, containing Belemnites Americana and Exogyra costata, 

 and lying in the region bordering on the Great Peedee and some of 

 its tributaries, as Black River, in a continuous area in Marion, Wil- 

 liamsburg and Georgetown counties. This formation was evidently 

 regarded by him as Cretaceous. (2) The next oldest formation of 

 marl, the Great Carolinian bed, so called by him because of a differ- 

 ence of opinion as to its age, Vanuxem, Conrad and Morton consid- 

 ering it Upper Cretaceous and Lyell including it in the Eocene. The 

 following observations were made in regard to this bed : That, though 

 the character of the bed changes from place to place, still for the 

 most part this marl is of a dingy yellowish white color, or pale buff 

 of different shades ; that the dip of the surface is generally from 

 north to south, and does not differ greatly from the general slope 

 of the country; that it extends from just east of the Santee to the 

 Savannah and beyond, its northwestern limit being a line almost 

 parallel to the line of falls of the rivers and about twenty-five or 

 thirty miles below, and that eastwardly it stretches to and beneath 

 the ocean and is overlaid in places by younger beds. (3) The Mio- 

 cene marls, occurring in extensive patches lying upon and immedi- 

 ately in contact with the older Pedee marls on the west side of Peedee 

 River and extending into Darlington and Florence counties, being 

 exposed along Swift and Black creeks. He also notes an isolated 

 patch of Miocene marl on Goose Creek a few miles above its junction 

 with Cooper River and about twelve miles from Charleston. 

 (4) Post-Pliocene marl beds, which lie between high and low tide 

 wherever yet (at that time) observed, probably with the exception 

 of that under and near Charleston. This formation generally pre- 

 sents but a thin bed, about three feet thick, containing the shells of 

 such animals as now live in and mostly if not entirely belong to the 

 neighboring ocean waters. Beds of post-Pliocene fossils were found 



